The Stovebolt Site Forums The Shop Area The Electrical Bay Bed not grounded?

I spent Saturday tracking down an electrical gremlin on my truck. The taillights were not working, and I finally traced the problem to the fact that the bed on my truck does not appear to be grounded. (?) If I grounded the taillight mount brackets to the bumper using a test lead, the lights would come on. I re-wired the two taillights and the license plate lamp, as well as removing the brackets and cleaning their connection to the body to ensure proper ground. I'm getting a solid 13 volts to the hot side of the connector. Despite all of this, I could not get the lights / signals to work until I ran a ground wire from the bed to the frame. It appears as if the bed is in contact with the frame in multiple places, so any ideas of why I saw the odd behavior? Thanks!

My bed is pretty rusty and the grounds weren't real hot. The brake light barely worked, and the blinkers you could only see if it was REALLY dark. I ended up going to NAPA and picking up one of those sealed plastic terminal boxes and running all of the grounds to that and exporting two ground wires to the headlight ground screws.

Works like a dream.

You should be able to run ground wires to any spot on the frame, though. You don't have to run the grounds all the way up to the front of the truck. The only reason I did it that way was because I knew that those grounds were good.

not odd behavior at all Troy, quite normal on an old truck, for the same reason you cleaned up the lights and their immediate mounting, you need to tend to the rest of the circuit - the bed 'sitting' on the frame is a real poor ground ... even where the bolts go thru is poor after a few years of slow galvanic corrosion building up - may look ok, but electricity ain't fooled

it's always a good idea to have a wire, well connected to cleaned spots, between the bed and the frame - same for the cab and the frame - as Brendan sez, the ground is critical to the proper flow of things

Bill

I am trying to locate a good spot to ground my bed to the frame. Where do you guys think is the best spot? In other words, what bolt on the bed is a good bolt to ground from to the frame? May I ask the same for the cab? What bolt on the cab is a good bolt to run a ground strap from the cab to the frame? The engine seems to be a little easier to find a bolt on. I like the bottom bolt that holds the starter on the engine. It's down under and not so noticeable.

Joe

on later trucks the factory put a ground strap [the flat braided type] from a starter bolt to a threaded hole on the toeboard part of the floor, like such, red X - for the bed I added a heavy wire from the frame to a hole I drilled on the back cross-sill, which is well bolted to the bed sides - use a good toothed star washer under both ends of it to dig in to the metal, same as the factory did on that cab ground - the frame will usually get a good ground from cab mounts, but it doesn't hurt to add one from a starter bolt

Red58 --

How heavy a ground wire did you use, 10-gauge or so?

that's plenty, even 12 or 14, and I use soldered on ends, not crimps - the current is minor for lights, doesn't take much if contact is good

Bill

Thanks for the info. On closer inspection the bolts that hold the bed to the frame are loose and the bed does appear to just be resting on the frame, which is no good for consistent grounding. I ran a 12 gauge wire with tinned ends / connectors from the area under the tailgate to the frame just underneath and this is working fine. I'll fix the bed issue when it comes off for restoration. The PO welded a metal plate over the existing bed wood and I need to figure out a clean way to get that out before I can easily remove the bed.